Direct numerical simulation of an stably stratified Ekman flow from the Incompact3D Code
DOI:
https://doi.org/10.5902/2179460X30712Keywords:
Direct numerical simulation, Ekman layer, Stable layerAbstract
In a diurnal cycle, distinct thermal and mechanical forcing generates different manifestations of a planetary boundary layer. The stable boundary layer occurs when the soil surface has a lower temperature than the air above. In this layer, wind shear is the main mechanism of turbulence generation. In the present study, a direct numerical simulation of an Ekman layer over a smooth wall is presented to investigate the different turbulent patterns that occur during evolution from a neutral boundary layer to a weakly stable boundary layer. The preliminary study shows the appearance of turbulent structures near the surface, due to the imposition of a stratification.Downloads
References
ANSORGE, C.; MELLADO, J. P. Global intermittency and collapsing turbulence in the stratified planetary boundary layer. Boundary-layer meteorology, Springer, v. 153, n. 1, p. 89–116, 2014.
CAUGHEY, S. J. Observed characteristics of the atmospheric boundary layer. In: Atmospheric turbulence and air pollution modelling. [S.l.]: Springer, 1984. p. 107–158.
CAVA, D.; MORTARINI, L.; GIOSTRA, U.; RICHIARDONE, R.; ANFOSSI, D. A wavelet analysis of low-wind-speed submeso motions in a nocturnal boundary layer. Quarterly Journal of the Royal Meteorological Society, Wiley Online Library, v. 143, n. 703, p. 661–669, 2017.
COLEMAN, G. N.; FERZIGER, J.; SPALART, P. A numerical study of the turbulent ekman layer. Journal of Fluid Mechanics, Cambridge University Press, v. 213, p. 313–348, 1990.
FRISCH, U. Turbulence: the legacy of AN Kolmogorov. [S.l.]: Cambridge university press, 1995.
GOHARI, S. I.; SARKAR, S. Direct numerical simulation of turbulence collapse and rebirth in stably stratified ekman flow. Boundary-Layer Meteorology, Springer, v. 162, n. 3, p. 401–426, 2017.
KAIMAL, J.; WYNGAARD, J.; HAUGEN, D.; COTÉ, O.; IZUMI, Y.; CAUGHEY, S.; READINGS, C. Turbulence structure in the convective boundary layer. Journal of the Atmospheric Sciences, v. 33, n. 11, p. 2152–2169, 1976.
LAIZET, S.; LAMBALLAIS, E. High-order compact schemes for incompressible flows: A simple and efficient method with quasi-spectral accuracy. Journal of Computational Physics, Elsevier, v. 228, n. 16, p. 5989–6015, 2009.
LAIZET, S.; LAMBALLAIS, E.; VASSILICOS, J. A numerical strategy to combine high-order schemes, complex geometry and parallel computing for high resolution dns of fractal generated turbulence. Computers & Fluids, Elsevier, v. 39, n. 3, p. 471–484, 2010.
LELE, S. K. Compact finite difference schemes with spectral-like resolution. Journal of computational physics, Elsevier, v. 103, n. 1, p. 16–42, 1992.
MORTARINI, L.; STEFANELLO, M.; DEGRAZIA, G.; ROBERTI, D.; CASTELLI, S. T.; ANFOSSI, D. Characterization of wind meandering in low-wind-speed conditions. Boundary-Layer Meteorology, Springer, v. 161, n. 1, p. 165–182, 2016.
SHAH, S. K.; BOU-ZEID, E. Direct numerical simulations of turbulent ekman layers with increasing static stability: modifications to the bulk structure and second-order statistics. Journal of Fluid Mechanics, Cambridge University Press, v. 760, p. 494–539, 2014.
SPALART, P. R.; COLEMAN, G. N.; JOHNSTONE, R. Direct numerical simulation of the ekman layer: A step in reynolds number, and cautious support for a log law with a shifted origin. Physics of Fluids, AIP, v. 20, n. 10, p. 101507, 2008.
SUN, J.; MAHRT, L.; BANTA, R. M.; PICHUGINA, Y. L. Turbulence regimes and turbulence intermittency in the stable boundary layer during cases-99. Journal of the Atmospheric Sciences, v. 69, n. 1, p. 338–351, 2012.
Downloads
Published
How to Cite
Issue
Section
License
To access the DECLARATION AND TRANSFER OF COPYRIGHT AUTHOR’S DECLARATION AND COPYRIGHT LICENSE click here.
Ethical Guidelines for Journal Publication
The Ciência e Natura journal is committed to ensuring ethics in publication and quality of articles.
Conformance to standards of ethical behavior is therefore expected of all parties involved: Authors, Editors, Reviewers, and the Publisher.
In particular,
Authors: Authors should present an objective discussion of the significance of research work as well as sufficient detail and references to permit others to replicate the experiments. Fraudulent or knowingly inaccurate statements constitute unethical behavior and are unacceptable. Review Articles should also be objective, comprehensive, and accurate accounts of the state of the art. The Authors should ensure that their work is entirely original works, and if the work and/or words of others have been used, this has been appropriately acknowledged. Plagiarism in all its forms constitutes unethical publishing behavior and is unacceptable. Submitting the same manuscript to more than one journal concurrently constitutes unethical publishing behavior and is unacceptable. Authors should not submit articles describing essentially the same research to more than one journal. The corresponding Author should ensure that there is a full consensus of all Co-authors in approving the final version of the paper and its submission for publication.
Editors: Editors should evaluate manuscripts exclusively on the basis of their academic merit. An Editor must not use unpublished information in the editor's own research without the express written consent of the Author. Editors should take reasonable responsive measures when ethical complaints have been presented concerning a submitted manuscript or published paper.
Reviewers: Any manuscripts received for review must be treated as confidential documents. Privileged information or ideas obtained through peer review must be kept confidential and not used for personal advantage. Reviewers should be conducted objectively, and observations should be formulated clearly with supporting arguments, so that Authors can use them for improving the paper. Any selected Reviewer who feels unqualified to review the research reported in a manuscript or knows that its prompt review will be impossible should notify the Editor and excuse himself from the review process. Reviewers should not consider manuscripts in which they have conflicts of interest resulting from competitive, collaborative, or other relationships or connections with any of the authors, companies, or institutions connected to the papers.
